Building Science Insights

Building Science Insights are short, informal discussions that highlight one or more building science principles. Like all BSC publications, they are grounded by solid research and experience. Unlike most BSC publications, however, they may also feature anecdotes, opinions, and even a joke or two (or three…).

Lively and engaging, Insights provide a fresh perspective on important industry issues. Enjoy them with your morning coffee or any time you need to wake up your building science brain.

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An edited version of this Insight first appeared in the ASHRAE Journal. The perfect wall is an environmental separator—it has to keep the outside out and the inside in. In order to do this the wall assembly has to control rain, air, vapor and heat.

An edited version of this Insight first appeared in the ASHRAE Journal. Buildings today are hollow and multi-layered with numerous air gaps or void spaces. Chases, shafts, soffits and drops abound. Everything is connected to everything else, typically unintentionally.

An edited version of this Insight first appeared in the ASHRAE Journal. Perhaps it was the drug culture of the 60’s that turned brains into coleslaw but it is hard to understand the lunatic practice of placing a layer of sand over the top of a plastic ground cover under a concrete slab in California.

An edited version of this Insight first appeared in the ASHRAE Journal. Ever wonder how we can build a 50 story glass tower that doesn’t leak, but we can’t seem to build a two-story house that doesn’t leak? The answer is a little bit of counter intuitive thinking.

When I see a fully glazed, floor-to-ceiling commercial or institutional building, I see an energy-consuming nightmare of a building that requires lots of heating and cooling at the perimeter just to maintain comfort. The result, on a cold winter day, is that offices exposed to the sun require cooling, while those in the shade need heat.

An edited version of this Insight first appeared in the ASHRAE Journal. Many “green” buildings don’t save energy. Why? They have too much glass, they are over-ventilated, they are leaky to air, they are fraught with thermal bridges and they rely on gimmicks and fads rather than physics.

An edited version of this article was first published in the ASHRAE Journal.
I have loved bourbon for a long time. I like the history. And I like the independent spirit of the folks who make it, their sense of tradition, and their willingness to continue to experiment. Even now after two hundred years of history, they experiment mostly by trial and error rather than by computer simulations. I have often thought that if engineers were in the liquor business, bourbon would be the liquor they would make.

An edited version of this Insight first appeared in the ASHRAE Journal.
Think of the good old days—the Civil War, WWI, the Great Depression, WWII—crawlspaces were uninsulated. They were ventilated and they didn’t have ground covers—and they didn’t have problems. Why?

An edited version of this article was first published in the ASHRAE Journal. In this Building Science Insight, Joseph Lstiburek discusses fundamental building physics applied to wine cellars and the storage of wine.

An edited version of this Insight first appeared in the ASHRAE Journal. Water causes enough trouble by itself, but when we add salt we go to a whole different level, especially where porous materials are concerned. What is the deal with porous materials? Simple, porous materials are capable of wicking water large distances due to capillary suction. And when water can move large distances only bad things can happen.

This article was first published in "Perspectives," Volume 17, Number 1. Spring 2009. The on-going consumption of energy to operate, condition, and light a building, as well as the energy embodied in on-going maintenance is the largest single source of environmental damage and resource consumption due to buildings. Reducing the operational energy use and increasing durability should be the prime concerns of architects who wish to design and building “green” buildings.

An edited version of this Insight first appeared in the ASHRAE Journal. So what do you do when you have an old building and the walls aren't doing their job? What do you do when the walls look bad, leak and are falling apart? You give them a face-lift.

The future is uncertain. This is a truism, and yet, when we design and construct a new building, we need to make decisions in the present or very near future. In fact, this is one of the critical distinctions about designing buildings: they are expected and likely to last 50 to 100 years, but we build them now. The challenge of designing for the future is no more acute than in the current choices facing the designer of an environmentally friendly building.

This Insight is an excerpt from Armin Rudd's "Ventilation Guide." This publication can be ordered online from www.buildingsciencepress.com. Experience is a great teacher, but much bad experience can be avoided through education. That is the goal of this Insight. Following some basic, uncomplicated design guidelines can go a long way to avoiding most trouble spots.

An edited version of this Insight first appeared in the ASHRAE Journal. Whenever there is a complaint about air quality in a building the first thing folks want to do is test the air. That is absolutely the worst thing to do. You do not start with air testing. I blame Star Trek. We grew up watching Spock go into a shuttle bay, do a tricorder scan and figure out that a tachyon field was causing the dilithium crystals to break down and that’s why Uhura had a headache. In Star Trek you could measure everything and anything. That’s not the way the real world works.

An edited version of this Insight first appeared in the ASHRAE Journal. You have got to love salesmen. They figure things out way before physicists, usually before engineers and certainly before greenie weenies. They found, what we should all know, that it is much more cost effective to fix the enclosure so that the actual system that you need is small and therefore does not cost much to install and does not cost much to operate. Oh, by the way, this approach also saves energy. Who knew?

An edited version of this Insight first appeared in the ASHRAE Journal. Over the years the big white Superdome roof that dominated the skyline of New Orleans apparently proved to be an irresistible target for folks with weapons. Hundreds of bullet holes were found when the roof of the Superdome was replaced after Hurricane Katrina.

An edited version of this Insight first appeared in the ASHRAE Journal. Energy security is pretty easy to get a handle on—don’t buy oil from the Middle East, Russia, Nigeria and Venezuela. The problem is that it is not cheap energy and it is not clean energy. We can make it clean, and we will, but it will be even more expensive. And actually that is good because we won’t waste it when it is expensive.

An edited version of this Insight first appeared in the ASHRAE Journal. Sometimes things are so obvious we miss them. The Second Law of Thermodynamics is like that. Most of us get the heat goes from warm to cold thing. It’s the other simple applications of the Second Law that we miss.